The present invention relates to a magnetic disk drive.
A magnetic disk drive, such as a hard disk drive (HDD), rotatably supports a magnetic disk.
FIG. 2 is a top view showing a typical HDD. FIG. 3 is a cross sectional view taken along line X-X of the HDD shown in FIG. 2. As shown in FIGS. 2 and 3, a magnetic disk 10 is rotatably supported in this HDD by being clamped by and between a motor hub 30 and a clamp member 40.
FIG. 4 is a cross sectional view showing an example of a conventional motor hub used in this HDD. Referring to FIG. 4, the conventional motor hub 30 has been formed so as to include a disk receiving surface 32 that makes a surface contact with a surface of the magnetic disk 10 and provides a support therefor.
The disk receiving surface 32 has been formed as detailed in the following in consideration of flexure of the motor hub 30 occurring as a result of weight of the magnetic disk 10 when the magnetic disk 10 is secured. Specifically, the surface 32 is an inclined surface having a head m forming an inclined angle α that corresponds to an angle of the flexure over a distance between an inner peripheral position and an outer peripheral position. The inner peripheral position is an inner radius a away from a rotational axis A of the magnetic disk 10. The outer peripheral position is an outer radius b away from the rotational axis A of the magnetic disk 10. A known system is disclosed in Japanese Patent Laid-open No. 2002-298479.